


Sister Counsel

by quitemagicaph



Category: Shadowhunters (TV), The Mortal Instruments Series - Cassandra Clare
Genre: Alec Lightwood/Izzy Lightwood, Drabble, I Don't Even Know, I Wrote This Instead of Sleeping, Insecure Alec, Izzy is a queen, M/M, Mentions of sexy stuff, Sibling Bonding, inspired from s2ep07's trailer, protect him pls, s2ep07 headcanon, sibling goals
Language: English
Status: Completed
Published: 2017-02-11
Updated: 2017-02-11
Packaged: 2018-09-23 15:31:33
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,629
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9663659
Author URL: https://archiveofourown.org/users/quitemagicaph/pseuds/quitemagicaph
Summary: "How do you know that it's the right time?" Alec tries, his eyes looking anywhere but his sister's."Oh my God."Izzy's mouth falls open, its sides quirking up just slightly the moment realization strikes her. Her whole body goes slack and she takes one step back, holding up her hands as if in defence. Alec's cheeks are a bright pink, burning up his face and he feels so hot he swears the temperature in the room has gone up fifty degrees. Izzy's reaction is not to be determined, since he sees her initial blantant confusion transform into pure shock. She lets out a short laugh before speaking again."Alec, are you talking about having sex?""Maybe."(or, Alec wants to take his and Magnus' relationship to the next level, but reaches out to Izzy first.)





	

**Author's Note:**

> I should have posted this much earlier, but life happens sometimes and ruins all of my plans.
> 
> I couldn't stop thinking of how Alec's talk with Izzy would play out, so here I am now.
> 
> Happy reading! :)

Alec already regrets his life decisions.  
  
Him approaching Isabelle intending to ask her for relationship advice is a very, very bad idea. It's not like she isn't trustworthy, Alec just knows that once he tells his little sister that he's planning on having sex with Magnus, she won't ever stop teasing him about it.  
  
Like, ever.  
  
By the time she finds out, and gets over the initial shock that Alec is sure will see taking over her as soon as he drops the news, there's no way she will shut up about it.  
  
And it will be only a matter of time before Jace finds out, too.  
  
Alec's stomach clenches.  
  
He still needs to lecture him on both his horrible tedency to always show up at the worst possible timing and him leaving the Institute, not intending to go back any time soon.  If it weren't for Alec being there when Jace showed up at his doorstep, Magnus would have kicked him out without sparing a second thought. But Alec was there, and mere seconds before Magnus was kissing him back with a sincerety he didnt know existed, while their broken, heavy voices promised they would put serious effort into smoothing out their differences. And, if Alec wants to be honest, Magnus definetely didn't seem like he could make rational decisions at that point, Alec's words and actions instantly forcing his wards to come down and forget to stand tall again.

(If Alec is immensely glad he managed to throw Magnus so off guard with such a simple gesture, no one has to know.)

But it's not like he would blame Magnus if he did throw him out. Jace finding shelter in his loft wasn't a good decision. Yes, Victor did treat him poorly, as Izzy told him, but that shouldn't be a good enough reason to leave. He's letting Aldetree win that way. He didn't survive Valentine's abuse and mind games to come back safe and somewhat healthy, and then leave again, giving in to Aldetree's own way of abusing, after all that everyone did to bring him back. And since he was so determined on leaving, did he  _really_ have to interrupt Alec and Magnus? He could have waited an hour. Or a couple of them.  
  
Although Alec isn't sure where that little moment would have gone to if it weren't for the unexpected visitors.  
  
And in the midst of it all, Alec doesn't understand how Jace seemed so unbothered when he walked in to find them breathing in one another, too enclosed into their own little relationship bubble to care about invading each other's personal space. He just doesn't get it, how was he so calm? Alec's his heart was pounding so loud in his chest he could almost swear people within meters of distance would be able to hear it. His ribcage was being broken open, his stomach had sank far down inside his body, all because of the few, short seconds Magnus' lips was on his.  
  
Alec is beyond screwed.  
  
Even as he is looking at Isabelle minding her own business, too focused on the small, flat screen on her palms and the task she was completing to notice Alec's piercing, weary stare, he knows he will regret asking. He can't help it, though, he needs his sister's opinion. His nerves are killing him.  
  
It's not the first time Alec feels insecure; in fact, everyone (literally, _everyone_ ) would agree that his deep set and scarring self esteem issues have formed Alec into the person he is now. What is the first time, though, is him reaching out to share his worries with someone, in this case, Isabelle, who has continuously tried to make him believe she's always going to be the best listener and let Alec go on endless ranting sessions to feel better.  
  
Well, it is also his first time having sex that's coming up, so it's double the pressure now.  
  
Izzy has a deep scowl set on her face, probably frustrated with all the recent demonic activity that has been spotted in the Institute's near vicinity and that she now has to report and do research on, when Alec speaks. He looks away from the bright screen he is facing at, closing the city map he was skimming through.  
  
He takes a few small steps towards the table Izzy is perched on.  
  
"Too many demons lately?" he asks, initiating a conversation with his sister.  
  
"Tell me about it. Seems like wherever these demons are coming from, they have one target, and that is to attack the Institute. I'm worried it's not long before they break the wards again," she sighs, dark eyes briefly drifting up to look at Alec before landing back on the screen.  
  
"It's no use, they still managed to get in even when Magnus' protections were perfectly effective. And we all saw where that got us."  
  
Izzy looks up at that, sensing Alec's regret and guilt in the way his voice got quiet, letting his eyes fall down to his shoes as his memories of the previous week's events making their way back to his brain. Alec presses his lips together and shakes his head lightly, as if to blur away the haunting nightmares.  
  
"It's not you fault, you know that right? You couldn't have done anything to avoid the possession." she says, stepping off the table and letting her tablet down. "Believe me, I speak from personal experience."  
  
"Yeah, how's your shoulder, by the way?" he questions, solely to drift the attention off of him. He knows Izzy is all healed up.  
  
"Almost brand new, I had even forgotten the wound is there in the first place." she smiles widely, proud of her fast healing.  
  
"Good to hear, it was a quite unpleasant stab."

There's a small pause during which Alec ponders how to ask his questions without making a fool of himself or sounding too desperate. The silence is broken by Izzy.  
  
"How was your date with Magnus? Did you guys hit it off?" she winks and Alec gapes at her. He probably looks like the impersonation of a question mark by now, but how does Izzy know? "Jace told me, by the way. Said he walked in on you two being cosy."  
  
"That's not what happened."  
  
"So you WERE being cosy! Dammit, I owe Jace ten bucks. I wouldn't believe him so he made me bet." Izzy presses her mouth into a thin line to fake discontentment, but it's pointless because she's still smiling brightly at Alec. She earns an eye roll from her brother, even though Alec can't help the blush that's creeping up his cheeks at the memory of their kiss.  
  
That kiss was barely anything more than a brush of their lips, yet it still turned Alec to mush.  
  
"You're unbelievable," he shakes his head.  
  
"You still haven't answered my question. You are not getting away that easily, big brother!" she chuckles, her eyes glinting with joy.  
  
"It was, uh, okay, I guess. Could've gone better." he replies, keeping the details to himself.  
  
"He beat you at pool, didn't he?"  
  
"Okay, how do you know about _this_ , as well?" he exasperates, furrowing his brows in curiocity.  
  
"I have my sources." she flicks her hair at her comment, staring at Alec with eyes full of mischief.  
  
"He must have used his magic, okay? There's no way he won without his thing," Izzy stares amusingly as Alec waves his wrist around in a swift, circular motion, trying to mimick Magnus' flourish.  
  
"Or you just let him win."  
  
Alec gasps. "No I didn't?" he's full on scowling at Izzy. She laughs, tipping her head back as she does.  
  
"Whatever. I'm just glad you had fun." she says softly in return, reaching over to squeeze Alec's hand. "You and Magnus make a great pair."  
  
She picks her screen back up and is about to go back to working on her report, but Alec stops her.  
  
"Actually, um. About that? I wanna ask you something. Well, actually. I need your advice." he dips his head lower, his embarassment making him unable to look at the eyes of his sister. Izzy cocks up one brow, offering a crooked grin.  
  
"What type of advice?"  
  
"Relationship, kinda."  
  
"HOLD UP." Izzy takes a few steps back, dumping the tablet on the table with a loud clank. "Is Alec Lightwood, a sworn protector of his personal life till the day he dies, also known as my grumpy older brother, asking me for relationship advice?" She then raises both her arms up, as if to pray, before letting them down again, resting her palms atop her heart in mock gratitude. "What did I do to earn this blessing of a treatment?"  
  
Alec averts his gaze from resting on his sister and sighs audibly. He can't say he didn't expect Izzy to overreact, yet the visual confirmation is all he needs to regret even trying to ask, in the first place. Maybe he should straight up ask Magnus about it, since he's the one who will be actively involved in the whole... process.  
  
Not that this would save Alec from humiliation and embarassment to the point of wanting to be stripped off his runes and live among the mundanes.  
  
Okay, maybe he's lying. He wouldn't ever willingly escape into the mundane world. Humans are stupid.  
  
"Nevermind, forget it. I shouldn't have asked," he mumbles, about to turn his back on Izzy and walk away. Izzy moves fast and catches up to him, stopping right in front of Alec to force him to stop.  
  
"Hey hey hey, calm down. I'm just messing with you," she offers smiling up at him. Classic Alec, taller than the most, always towering over everyone. "What's the matter?"  
  
"Promise me you won't joke around."  
  
"I won't joke around."  
  
"I'm serious."  
  
"So am I. Oh come on, Alec. You can tell me anything, I'm your sister, remember?" she sighs, and Alec indeed needs to remember that next time he feels so weary of opening up to her. For now, though? He's not so sure he shouldn't be cautious.  
  
Alec gulps dryly, hands already getting sweaty both because of the conversation that's about to take place and the images and thoughts this conversation will torture him with.  
  
The truth is, Alec has thought of him and Magnus having sex before. He has thought of them lying on Magnus' king sized bed, tangled between satin sheets, him underneath Magnus, squirming, letting him wreck him to pieces. He has thought of how it would feel like to be inside of Magnus, having him enclosed inside the prison of his arms while he pins him down on the matress and makes him scream his name in pleasure. Or how extra breathtaking Magnus would look when he was riding out an orgasm Alec caused.

(Don't blame Alec, okay? Sometimes he lies awake in bed for far longer than he should, and his brain goes wild. Along with other parts of his body.)  
  
He thinks of them more than he would ever like to admit. And now that there are actual chances of getting to witness this whole thing with Magnus, Alec feels his heart jump and his fingers tingle.  
  
"You have dated a bunch of people so far, right?" he ends up asking, finding it hard to get straight to the point.  
  
"A few. Enough to know anything my precious brother would care to ask about," she grins, nudging him on his ribs. She then places crosses her arms over her chest, silently urging Alec to continue.  
  
"Well, with these people, when d- i mean, how did you know when it was time?" he blurts out, cheeks now burning a bright pink. Alec fidgets with his jacket sleeves, busying his hands.  
  
"Elaborate."  
  
Alec sighs.  
  
"I mean..." he drifts off, letting his words jump around in between them, until he finds the right ones to use.  
  
"Okay, like, once you find them. The person, I mean. How did y- how do you know that it's the right time?" Alec tries, his eyes looking anywhere but his sister's.  
  
"Oh my God."  
  
Izzy's mouth falls open, its sides quirking up just slightly the moment realization strikes her. Her whole body goes slack and she takes one step back, holding up her hands as if in defence. Alec's cheeks are a bright pink, burning up his face and he feels so hot he swears the temperature in the room has gone up fifty degrees. Izzy's reaction is not to be determined, since he sees her initial blantant confusion transform into pure shock. She lets out a short laugh before speaking again.  
  
"Alec, are you talking about having sex?"  
  
"Maybe."  
  
"ALEC, OH MY GOD, ARE YOU TALKING ABOUT HAVING SEX WITH MAGNUS?" she half screams, and now Alec, more embarrassed than ever, reaches over to cover Izzy's mouth with his hand. Izzy laughs harder at that -she's practically full on giggling- and even she is blushing a little, a soft rosy color tinting her round cheeks, but she stops abrubtly once she observes the seriousness on Alec's expression.  
  
"Can't you stay quiet? It's already hard enough, you going about screaming isn't helping." he tells her, trying to keep his voice from shaking. "It's not such big of a deal, anyway."  
  
"But Alec," she protests. "It is a big deal. It's an hugely awesome deal, in fact. I hadn't realized things between you and Magnus were serious and I can't begin to explain how glad I am they are." she smiles, and Alec knows she means it. Izzy has been persuading him to speak up about Magnus since the first day the two met and Magnus was flirting relentlessly.  
  
"I don't wanna burden you or anything, you know, by asking." he says simply and earns a disapproving shake of the head from Izzy.  
  
"Won't you give this up already? How many times have I mentioned how happy I am you reached out to me? It's truly honoring." she says, and gently grabs on both of Alec's upper arms, squeezing lightly. Alec smiles faintly upon the contact.  
  
"So, let's get down to business," she lets go before clasping her palms together and cracking the knuckles, as if she's about to get on a physical fight. _Dramatic_ , Alec thinks. "What do you wanna know?"  
  
"Answer my question first off," Alec says back, raising his brows.  
  
Izzy chuckles. "Okay. If you want to know, I don't think there's a wrong or right time. If you both want this, if you both feel ready for it, then there's nothing that can stop you. Have you two discussed it?"  
  
"No, not yet. I wanted to ask an outsider first, before Magnus."

"I'm an outsider?"

" _You know what I mean,_ " Alec shoots back, frustrated.  
  
"I'm kidding, tone it down a notch. As I was saying, before else, you need to know whether you both are on common ground." the stability in Isabelle's eyes makes Alec slightly nervous. How, in the name of the Angel, will he bring that up to Magnus? He feels another blush form high on his cheekbones. "You might feel ready for it, that doesn't mean he is too. So, speak up. Consent is the key."  
  
"That's reasonable." Alec thinks.

"It is, isn't it?" says Izzy, bragging. Alec proceeds to speak again.

"I wish that was the only problem, though," he pauses, suddenly running out of breath. "Magnus... He has done it before. Many times, with many people."  
  
"Yeah, so?"  
  
"What if I- I don't know, do something wrong and mess it up? He has experience, Izzy, I don't. I would hate to mess it up. It feels right, I want us to-" another pause, "move on, get there, if of course he wants it, too. Magnus- he deserves so much more than I could give."  
  
And _wow_ , Alec cannot believe he said these words aloud.  
  
But it's the absolute truth.  
  
Magnus has been around for more than his own self probably remembers. The number of people he has acquainted, the number of said people he has actually been involved with, is still far too big for any mortal human being. Magnus, Alec believes, must have soaringly high expectations, given the current situation. Magnus surely has favorite ways to be touched, favorite places to be kissed, soft spots all over his body that make him go weak at his knees and that thought alone terrifies Alec. He wants (no, he _needs_ ) to worship Magnus' body in all its glory, and God, would he want to discover new places to kiss. Alec wants to make their time together perfect, or as perfect it can be for both of them because Magnus deserves to be appreciated like the artpiece he denies himself to be, and he wishes his own inexperience wasn't an obstacle to that.  
  
That's why he asked Izzy, aside from the reliability she swears on. She isn't the only one with exes, Jace has a bunch of them himself but Alec wouldn't ever ask him. He hoped his sister would understand him, and she did; and Alec is relieved. Yet his heart can't stop beating louder every time he thinks about the high percentage possibility of him messing it all up and disappointing Magnus.  
  
(What he doesn't know, is that Magnus is equally terrified and stressed out of his mind that he will too disappoint Alec. Magnus hasn't been someone's first in a really, really long time and Alec, even if he is a Shadowhunter who's been training and fighting his whole life, feels so fragile, so breakable and pure to him.  
  
He's still afraid Alec will walk out, as he almost did, twice already. He dreads the moment Alec decides Magnus isn't worthy and runs away, stomping his heart in the process.)  
  
He lets out one shaky breath, as Izzy stares at him in disbelief.  
  
"Wow, Alec. I love you, I truly do, you're my brother and all that, but are you that stupid?" she blurts out and her brows stitch together in confusion.  
  
"Thank you for your unconditional support."  
  
"Alright, Alec, listen up. You and Magnus clicked. From the very first minute he introduced himself to you, everyone could tell that something huge and meaningful was about to happen. You are unlike any other couple I have seen, and you have been dating for what? A couple of weeks? You worrying sick that you will fail to make Magnus feel good is complete nonsense. Your first time having sex with someone you deeply care for isn't going to be perfect. It never is. It never will be. Think of it less like an immaculate moment you will remember and cherish forever and more like an introduction to what you and Magnus both individually and as a whole enjoy. It doesn't have to be flawless, because it won't be. Practice and time makes it as perfect, and pleasurable as it can get. And seriously, Alec, if you believe Magnus would ever be disappointed in you then you don't know him and how he feels for you at all." Izzy finishes, her face stern with seriousness.  
  
And, well. Alec is speechless. He can still distinguish the sickly feeling of anxiety pooling in his stomach, but now his shoulders are much more slack, his whole posture has relaxed. Izzy's earnest words hit him right where they needed to and he lets out another nervous sigh, letting his eyelids drop shut as he does.  
  
"Don't worry. It will be okay. All you need to do is ask him." Izzy smiles, exposing her perfect, pearly white teeth.  
  
"Thanks, Iz." he manages to say, but figures she understands he owes her so much more than just a thank you.  
  
"You're very much welcome." she cheers. "Now, as much as I loved this little sibling bonding session we had," she points at the space between them, "I seriously need to get back to work. Aldetree is breathing down my neck, he needs the recent demonic activity report."  
  
"Sure, yeah. Do that. I'll probably stop by Magnus' anyway."  
  
"Are you gonna ask now?"  
  
"Well, I have to talk to Jace, first of all. I'll deal with Magnus later." he says, determined.  
  
As Alec is about to turn his back to Izzy and walk away, he stops right on his heels and gives it a second thought. Izzy, who had her tablet back in hand, was left astonished when Alec quickly paced towards her and wrapped his arms around her back, hugging firmly. Alec holds his sister in his arms for a few seconds, trying to pass on his gratitude through touch. He feels Isabelle's distinctively smaller arms make their way to his lower back, squeezing back.  
  
Alec smiles. Izzy will never stop driving him crazy out of his mind, yet he's wholeheartedly thankful to have her.  
  
"I can't believe I got you to open up  _and_ give me a hug on the same day. Who are you and what did you do to my brother?" she laughs and lets go of the hug.

"You're ridiculous."

"Love you too." Alec then grins wide, and heads towards the exit of the Institute. He wasn't lying when he said he needs to confront Jace from moving out.

"Oh, Alec?" Izzy calls out.

"What now?" he turns his head to look at her.

"Lock your doors once you get to the heated stuff. Jace is lurking." she winks. "Plus, I'm sure he wouldn't want to be scarred for eternity by walking in on you blowing Magnus."

"You're far more than just ridiculous." he snorts and instantly hates the images that pop up in his head because of Izzy's detailed argument. 

"And use protection!" Izzy shouts at last, but Alec is already walking away, smirking to himself.

**Author's Note:**

> I'm sorry if you found any typos, or mistakes, it's literally 1 am and I'm exhausted.
> 
> Find me on [Tumblr](http://divines-move.tumblr.com/) and [Twitter](https://twitter.com/maIecwolves/) if you wanna, like, come say hi or something. 
> 
> (Which you totally should. Just saying.)


End file.
